1. Field of the Invention
The present invention relates to electrical connectors and more particularly to electronic power connectors especially, useful in circuit board or backplane interconnection systems.
2. Brief Description of Prior Developments
Designers of electronic circuits generally are concerned with two basic circuit portions, the logic or signal portion and the power portion. In designing logic circuits, the designer usually does not have to take into account any changes in electrical properties, such as resistance of circuit components, that are brought about by changes in conditions, such as temperature, because current flows in logic circuits are usually relatively low. However, power circuits can undergo changes in electrical properties because of the relatively high current flows, for example, on the order of 30 amps or more in certain electronic equipment. Consequently, connectors designed for use in power circuits must be capable of dissipating heat (generated primarily as a result of the Joule effect) so that changes in circuit characteristics as a result of changing current flow are minimized. Conventional plug contacts in circuit board electrical power connectors are generally of rectangular (blade-like) or circular (pin-like) cross-section. These are so-called “singular-mass” designs. In these conventional singular-mass blade and pin configurations, the opposing receptacle contacts comprise a pair of inwardly urged cantilever beams and the mating blade or pin is located between the pair of beams. Such arrangements are difficult to reduce in size without adversely effecting heat dissipation capabilities. They also provide only minimal flexibility to change contact normal forces by adjustment of contact geometry.
There is a need for a small contact which efficiently dissipates heat and which has readily modifiable contact normal forces.
In the parent application for the present application, namely U.S. patent application Ser. No. 09/160,900, electronic power connectors are described for use in power circuits where the connectors provide terminations associated with power that is internal to the system. In some power circuit configurations an external power supply, usually an external AC power cable, may also be incorporated into the overall environment. The external AC power supply connections are known to be stand-alone cable connections that are terminated directly onto the board. This poses known drawbacks due to the fact that in those circumstances where the AC power supply is on the order of 30 amps or more an undesirable level of heat buildup on the traces of the power board can occur. Also, where stand-alone cable connections are used to adapt AC power by direct wire termination onto the power distribution boards there is an additional level of complexity in the connective configurations on the board. Thus, there is a need for an electronic power connector that incorporates into a single housing those contacts for establishing connections for the internal system power and contacts for mating with an external power cable.